Rust setup script to automatically install the correct toolchain, components, and tool crates

crate-bin-setup

#!/usr/bin/env bash
set -eEuo pipefail
# Should live as: {{project}}/bin/setup
# Requires:
# - {{project}}/.config/setup-install-tool-crates.txt
# - {{project}}/rust-toolchain.toml

cd "${TOP_DIR:-$(cd "$(dirname "$0")" && cd .. && pwd)}"

readarray -t packages < <(sed 's/#.*//;/^[[:space:]]*$/d' .config/setup-install-tool-crates.txt)
toolchain=$(sed '/channel/!d;s/"$//;s/.*"//' rust-toolchain.toml)
readarray -t components < <(sed '/components/!d;s/"]$//;s/.*\["//;s/", "/\n/g' rust-toolchain.toml)

has() {
  command -v "$@" &>/dev/null
}
die() {
  echo >&2 "$@"
  exit 1
}
rustup_component_list() {
  rustup component list --toolchain "$1" |
    sed '/installed/!d;s/[[:space:]].*//'
}
list_includes() {
  local -n arr="$1"
  local val="$2" i
  for i in "${arr[@]}"; do
    [[ "$i" = "$val" ]] && return 0
  done
  return 1
}
cargo_install() {
  echo "cargo install $1 --locked"
  cargo install "$1" --locked
}

sccache_checked=
check_sccache() {
  if [[ "$sccache_checked" = 1 ]]; then
    return
  fi
  sccache_checked=1

  if ! has sccache && list_includes packages sccache; then
    (
      unset RUSTC_WRAPPER
      cargo_install sccache
    )
  fi
}

has cargo || die 'Cargo is not installed. Please install Rust and Cargo first.'
has rustup || die 'Rustup is not installed. Please install Rustup first.'

if ! rustup toolchain list | grep -q "^$toolchain-"; then
  echo "Installing Rust toolchain $toolchain..."
  rustup toolchain install "$toolchain"
fi

for c in "${components[@]}"; do
  if rustup_component_list "$toolchain" | grep -q "^$c-"; then
    echo >&2 "Rust component $c is already installed, skipping."
    continue
  fi
  echo "Installing Rust component $c..."
  rustup component add --toolchain "$toolchain" "$c"
done

for p in "${packages[@]}"; do
  if cargo install --list | grep -q "^$p v"; then
    echo >&2 "$p crate utility is already installed, skipping."
    continue
  fi

  check_sccache
  [[ "$p" = sccache ]] || cargo_install "$p"
done